Class JDesktopPane

A container used to create a multiple-document interface or a virtual desktop. You create JInternalFrame objects and add them to the JDesktopPane. JDesktopPane extends JLayeredPane to manage the potentially overlapping internal frames. It also maintains a reference to an instance of DesktopManager that is set by the UI class for the current look and feel (L&F). Note that JDesktopPane does not support borders.

This class is normally used as the parent of JInternalFrames to provide a pluggable DesktopManager object to the JInternalFrames. The installUI of the L&F specific implementation is responsible for setting the desktopManager variable appropriately. When the parent of a JInternalFrame is a JDesktopPane, it should delegate most of its behavior to the desktopManager (closing, resizing, etc).

For further documentation and examples see How to Use Internal Frames, a section in The Java Tutorial.

Warning: Swing is not thread safe. For more information see Swing's Threading Policy.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans™ has been added to the java.beans package. Please see XMLEncoder.

Fields

LIVE_DRAG_MODE

public static final int LIVE_DRAG_MODE

Indicates that the entire contents of the item being dragged should appear inside the desktop pane.

See Also:

OUTLINE_DRAG_MODE, setDragMode(int), Constant Field Values

OUTLINE_DRAG_MODE

public static final int OUTLINE_DRAG_MODE

Indicates that an outline only of the item being dragged should appear inside the desktop pane.

See Also:

LIVE_DRAG_MODE, setDragMode(int), Constant Field Values

Constructors

JDesktopPane

public JDesktopPane()

Creates a new JDesktopPane.

Methods

getUI

public DesktopPaneUI getUI()

Returns the L&F object that renders this component.

Returns:

the DesktopPaneUI object that renders this component

setUI

public void setUI(DesktopPaneUI ui)

Sets the L&F object that renders this component.

Parameters:

ui - the DesktopPaneUI L&F object

See Also:

UIDefaults.getUI(javax.swing.JComponent)

setDragMode

public void setDragMode(int dragMode)

Sets the "dragging style" used by the desktop pane. You may want to change to one mode or another for performance or aesthetic reasons.

Parameters:

dragMode - the style of drag to use for items in the Desktop

Since:

1.3

See Also:

LIVE_DRAG_MODE, OUTLINE_DRAG_MODE

getDragMode

public int getDragMode()

Gets the current "dragging style" used by the desktop pane.

Returns:

either Live_DRAG_MODE or OUTLINE_DRAG_MODE

Since:

1.3

See Also:

setDragMode(int)

getDesktopManager

public DesktopManager getDesktopManager()

Returns the DesktopManger that handles desktop-specific UI actions.

setDesktopManager

public void setDesktopManager(DesktopManager d)

Sets the DesktopManger that will handle desktop-specific UI actions. This may be overridden by LookAndFeel.

Parameters:

d - the DesktopManager to use

updateUI

public void updateUI()

Notification from the UIManager that the L&F has changed. Replaces the current UI object with the latest version from the UIManager.

Overrides:

updateUI in class JComponent

See Also:

JComponent.updateUI()

getUIClassID

public String getUIClassID()

Returns the name of the L&F class that renders this component.

Overrides:

getUIClassID in class JComponent

Returns:

the string "DesktopPaneUI"

See Also:

JComponent.getUIClassID(), UIDefaults.getUI(javax.swing.JComponent)

getAllFrames

public JInternalFrame[] getAllFrames()

Returns all JInternalFrames currently displayed in the desktop. Returns iconified frames as well as expanded frames.

Returns:

an array of JInternalFrame objects

getSelectedFrame

public JInternalFrame getSelectedFrame()

Returns the currently active JInternalFrame in this JDesktopPane, or null if no JInternalFrame is currently active.

Returns:

the currently active JInternalFrame or null

Since:

1.3

setSelectedFrame

public void setSelectedFrame(JInternalFrame f)

Sets the currently active JInternalFrame in this JDesktopPane. This method is used to bridge the package gap between JDesktopPane and the platform implementation code and should not be called directly. To visually select the frame the client must call JInternalFrame.setSelected(true) to activate the frame.

Parameters:

f - the internal frame that's currently selected

Since:

1.3

See Also:

JInternalFrame.setSelected(boolean)

getAllFramesInLayer

public JInternalFrame[] getAllFramesInLayer(int layer)

Returns all JInternalFrames currently displayed in the specified layer of the desktop. Returns iconified frames as well expanded frames.

Parameters:

layer - an int specifying the desktop layer

Returns:

an array of JInternalFrame objects

See Also:

JLayeredPane

remove

public void remove(Component comp)

Overrides:

remove in class Container

Parameters:

comp - the component to be removed

See Also:

Container.add(java.awt.Component), Container.invalidate(), Container.validate(), Container.remove(int)

selectFrame

public JInternalFrame selectFrame(boolean forward)

Selects the next JInternalFrame in this desktop pane.

Parameters:

forward - a boolean indicating which direction to select in; true for forward, false for backward

Returns:

the JInternalFrame that was selected or null if nothing was selected

Since:

1.6

addImpl

protected void addImpl(Component comp,
                       Object constraints,
                       int index)

super.addImpl(comp, constraints, index)

Overrides:

addImpl in class JLayeredPane

Parameters:

comp - the component to be added

constraints - an object expressing layout constraints for this component

index - the position in the container's list at which to insert the component, where -1 means append to the end

Since:

1.6

See Also:

Container.add(Component), Container.add(Component, int), Container.add(Component, java.lang.Object), Container.invalidate(), LayoutManager, LayoutManager2

remove

public void remove(int index)

Remove the indexed component from this pane. This is the absolute index, ignoring layers.

Overrides:

remove in class JLayeredPane

Parameters:

index - an int specifying the component to remove

Since:

1.6

See Also:

JLayeredPane.getIndexOf(java.awt.Component)

removeAll

public void removeAll()

Removes all the components from this container.

Overrides:

removeAll in class JLayeredPane

Since:

1.6

See Also:

Container.add(java.awt.Component), Container.remove(int), Container.invalidate()

setComponentZOrder

public void setComponentZOrder(Component comp,
                               int index)

Overrides:

setComponentZOrder in class Container

Parameters:

comp - the component to be moved

index - the position in the container's list to insert the component, where getComponentCount() appends to the end

Since:

1.6

See Also:

Container.getComponentZOrder(java.awt.Component), Container.invalidate()

paramString

protected String paramString()

Returns a string representation of this JDesktopPane. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null.

Overrides:

paramString in class JLayeredPane

Returns:

a string representation of this JDesktopPane

getAccessibleContext

public AccessibleContext getAccessibleContext()

Gets the AccessibleContext associated with this JDesktopPane. For desktop panes, the AccessibleContext takes the form of an AccessibleJDesktopPane. A new AccessibleJDesktopPane instance is created if necessary.

Specified by:

getAccessibleContext in interface Accessible

Overrides:

getAccessibleContext in class JLayeredPane

Returns:

an AccessibleJDesktopPane that serves as the AccessibleContext of this JDesktopPane